The stepping exerciser known to applicant is US patent application with application Ser. No. 09/431,203. The stepping exerciser is illustrated in FIGS. 1 to 3 and includes a base 4 with a tubular member 42 connected thereto and two couplers 54 extend in opposite directions from the tubular member 42 so that two pedals 52 are respectively and rotatably connected to the two couplers 54. The two couplers 54 are rotatable about a central axis of a shaft 422 on which the couplers 54 are mounted. Two slots 421 are defined through the tubular member 42. A rotatable member 51 is received in the tubular member 42 and two extension members 511 extend from the rotatable member 51 and extend through the slots 421. Each of the extension members 511 has a sleeve 512 mounted thereon. Two connection rods 41 connected to the tubular member 42 so that two cylinders 53 are respectively connected to an underside of each of the pedals 52 and the two connection rods 41. When a user steps on the two pedals 52 and alternatively steps the pedals 52, the couplers 54 are rotated and the two extension members 511 are pushed by the pushing rods 541 extending from the couplers 54. By this way, the user can alternatively steps the pedals 52 downward and the cylinders 53 provide resistance for the exercising purpose.
However, because the two feet of users have different level of muscle forces so that the resistance may be too solid for one of the two feet. Therefore, the user feels that his/her body is inclined to one side because the foot on that side can step deeper than the other foot.
The present invention intends to provide a stepping exerciser wherein the depth of the pedals can be adjustable.